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All right, so let's illustrate the steps that take place when a client connects to an access point

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and then we can visualize how the data transmission works.

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So stay in a station, a client that wants to connect to an access point, AP represents that access

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point.

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Now, we can separate this process into three main parts, right, probe authentication and association.

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So in the probe process.

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The EPA first sends a probe on all channels to find the AP.

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And then the apps and range answer to the probe request.

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Of course, is the very first step of connection, so in this phase, the driver of the client searches

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for an AP.

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Then in the authentication process.

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The state sends an authentication request to the AP by default to the one with the best signal.

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And then it also checks the compatibility of the encryption type.

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Then once compatable networks are discovered, the station will attempt authentication with compatible

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access points.

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And then the access point will receive the authentication frame and then it responds to the station

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with the authentication frame set to open, indicating a sequence.

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If an access point receives any frame other than an authentication or a probe request from a station

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that is not authenticated, it will respond with a D authentication frame.

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And finally, in the association process, once the station determines which access point it would be

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most likely to associate with, it will then send an association request to that access point.

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And then if the elements of the association request match the capabilities of the access point, it

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will create an association I.D. for the station and then respond with an association response with a

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success message granting network access to that Mobil station.

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Now, the Steet or station can communicate with a network.

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So after all of this process is finally completed, that it can then be exchanged on the network.

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Now, please note that there is an other phase for an encrypted networks, there's a key exchange and

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verification that will happen just after association before you're able to use the network.

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All right, so now let's have a look at the authentication methods.

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Now, there are two types of authentication, the shared authentication, and it's only used with weap

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and open authentication.

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So the steps that take place during an open authentication are basically wireless client sends an authentication

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request to the access point.

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The access point then sends an authentication response and the authentication process is completed successfully.

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Shared key authentication is another method of authenticating with weapons labeled networks, so the

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station sends an authentication request to the access point.

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Access Point sends a challenge text to the station.

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The station then uses its default key to encrypt the challenge text and sends it back to the AP.

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The AP then decrypt the encrypted text with the Web key that corresponds to the station default key

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and then compares the result with the original challenge text if there's a match.

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Of course, that means they share the same key and the AP authenticates the station, if there's no

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match, the AP refuses to authenticate the station.

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So let's have a look at the association process in Wireshark.

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So I captured the packets of association processes that took place between a phone and my access point.

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So first, I filtered the results by applying the Mac address of the phone as the source address.

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Then the process takes place here, so probe request authentication and association packets, respectively.

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Then when we add a filter by playing the access point as the destination, we can see the response packets

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sent by the access point for the association process.